In the raising and feeding of animals continual vigilance must be maintained to notice any sickness. Sickness is usually accompanied by rise in body temperature. By the time the fever is evident by observation of an animal, the illness has often progressed too far to save the animal and other animals may have become infected. Heretofore, the means of measuring animal body temperature has been in the anal region. Such measurement has required confinement of the animal and thus is expensive. Experimentation has been undertaken in which an anal thermometer is used coupled with an exposed indicator that is permanently attached, for example, to the base of the tail; however, this type of fever indicating means has been limited to feed lot use, and has been extremely expensive.
It has been discovered that there exists a region of an animal's head near the juncture of the back portion of the ear and skull in which is formed a cavity protected by tissue including gristle and hide and further isolated at its lateral and under sides by tissue and bone so that the temperature therein is closely and accurately related to the animal's body temperature, in fact the difference being in the order of 1.degree. F.
This region may be more accurately described as follows: The area bounded cranially by the posterior border of the conchal cartilage and caudally by the anterior border of the cleido-occipitalis muscle. The area is composed of skin, sub-cutaneous fascia and fat. Furthermore, the cavity seems to provide a means whereby certain medicines may be introduced.